Compensating stairway.



Patented Jan. 11, 1916.

INVENTOR WITNESSES COLUMBIA PLANOGRAPH co.. WASHINGTON. D. c.

r ors on.

PRESLY J. FICKINGER. or CONNEAUT, OHIO.

COMPENSATING 'STAIRWAY.

T0 all whom it may concern: I i

Be it known that I, PRESLY J. FICKINGER, a citizen of the United States,and resident of Conneaut, in the county of 'Ashtabula and State of Ohio,have invented certain new and useful Improvements in CompensatingStairways, of which the following is a specification.

My invention relates to the construction of stairways for use inconnecting separated points on a moving or swinging member such as theillustrated construction in which the invention is applied to theoscillating beam of unloading mechanisms used in unloading. ore andsimilar bulk cargoes from ore boats and similar vessels.

One object of my invention is to provide a stairway of improvedconstruction having oscillatingtreads and having novel means whereby thetreads are maintained in substantially horizontal planes while thestairway is being swung through the arc of a circle. 7

Another object of the invention is to provide a movable stairway havingpivoted treads adapted to swing when the stairway is moved and remain assubstantially horizontal planes while the. stairway is being moved.

A further object of my invention is the provision of a stairway havingthe novel combination and arrangement of parts shown in the accompanyingdrawings, to be more fully described hereinafter, and to be specificallypointed out in the appended claims.

Referring now to the drawings, forming part of this specification,Figure 1 is a side elevation showing part of the oscillating beam of anore unloading mechanism with a stairway constructed and arranged andapplied for use thereon in accordance with my invention. Fig. 2 is asectional elevation showing a detail of the construction of the movabletreads and means employed in maintaining the flat top surface of thetreads in horizontal planes. Fig. 3 is a similar detail showing amodification in the means employed in maintaining the stair treads inparallel planes and horizontal position on the swinging arm or othermovable member to which the stairway is applied for use.

In the accompanying drawings, the numeral 2 designates the oscillatingbeam of an ore unloading apparatus which is pivoted on a shaft 3 so asto rock between the positions shown in full lines and in dotted linesSpecification of Letters Patent.

Patented Jan. 11,1916.

Application filed September 25, 1915. Serial No. 52,564.

lating beam 2 which is of built up construction is a compensatingstairway embodying my invention. This stairway comprises sides 4, which(as shown in Fig. l) are rigidly secured to extend in the-desired sitionfrom one end ofa platform 5 to the platform formed by the top coverplates .6 of the beam 2. A hand rail 7 provided on oneor both sides ofthe stairway and platform is usually employed for the sake of safety. ai

Secured to the sides 4 of my improved stairway to extend between theopposite faces" thereof are shafts or pins forming trunnions- 8 andpivotally connected to each trunnion is a stair tread 9. Each of thetreads 9 is provided on one end as shown with a downwardly extending armforming a lever 10 by which the series of treads are pivotally connectedto a link bar 11 which extendslengthwise parallel with the sides 4- ofthe stairway below the treads 9. Fastened to part of or when desired, toeach of the treads 9 are the ends of a U-shaped strap 12 the strap beingsecured to the treads so as to depend therefrom andon the depending orlower end of the U-shaped straps are heavy balance weights 13, theweights and the strap forming a pendulum which acts to -maintain theupper surfaces of the treads 9 angular poin Fig. 1. Secured on the sideof the oscilthus seen that a workman can ascend or descend between theplatforms 5 and 6 without reference to Y the angular position of thestairway and at any point in the swinging movement as the treads 9 willalways extend horizontally in all positions of the oscillating arm.

' In the modified construction shown in Fig. 3, the treads 9 areprovided with arms 10 by which they are connected to a link bar 11 inthe same manner as has been described. In this construction the U-strapsing movement of the stairway. As will be 7 seen in Fig. 3, the trunnion8 for one of the treads 9 is provided with a sprocket wheel 14 which iskeyed or otherwise fixed to the trunnion 8 to rock the trunnion. Thesprocket wheel 14 is connected to a second sprocket wheel 15 by theendless sprocket chain 16, and the sprocket wheel 15 is keyed orotherwise fiXed on the pivot pin 17 by which the upper ends of the sides4 of the stairway turning on the pivot pin 17 so that when the sidesmove angularly or swing the sprocket chain 16, sprocket wheel 14 andlink bar 11 causes the treads to move with respect to the sides 4 andthe upper surfaces of the treads are thereby maintained in substantiallyhorizontal planes.

The advantages of my invention will be apparent to those skilled in theart. My invention provides a compensating stairway which is applicablefor use on the swinging arms of ore unloaders and on the rocking membersof various structures and by the use of my invention a stairway isprovided in which the treads are always in the desired horizontalposition irrespective of the swinging movement of the structure to whichthe stairway is fixed so that it is safe and easy to ascend or descendthe steps even during the swinging movement of the stair way.

Modifications in the construction and arrangement of the parts may bemade without departing from my invention as defined in the appendedclaims.

I claim 1. In a stairway the combination with a swinging arm, of stairsides secured thereto,

2. A swinging stalrway comprising a series of treads, swinging means'towhich the treads are pivoted, means for swinging said pivoted treads 1nunison, and'a swlngmg welght whereby said treads are mamtamed inparallel, horizontal planes in the swinging movement thereof.

3. A swinglng stairway comprising aseries of treads, swinging means towhich the treads are pivoted, means for moving said pivoted treads inunison, and a depending weight whereby said treads'are maintained. 1.1.;

in parallel horizontal planes in the movement thereof;

4. A swinging stairway comprising a se: ries of treads, swinging meansto which the treads are pivoted, means for moving said I pivoted treadsin unison, means for moving said swinging means to which the treads arepivoted and a pendulum whereby said treads are maintained in parallelhorizontal planes in the movement thereof.

In testimony whereof I have hereunto set my hand. V

PRESLY J .FlGKINGER.

Copies of this patent may be obtained for five cents each, by addressingthe Commis'sioner'of Patents, Washington, D. 0. 1

